Sugar amine compounds



Patented Mar. 5, 1946 UNITED STATES PATEN I I 2,396,097 r OFFICE- SUGAR AMINE COMPOUNDS Ivan Gubelmann, Wilmington, Del., assignor to E. I. du Pont de Nemours & Company, Wilmington, De l., a corporation of Delaware No Drawing. Original application January 12, 1943, Serial No. 472,159. Divided and this application November 23, 1943, Serial No. 511,477

Claims. (Cl. 260-211) This invention relates to the stabilization of organic substances and particularly to the stabillzation of such substances which are subject to deterioration imparts undesirable qualities to them and eventually destroys their usefulness.

Signal success has been achieved in recent years, in the preservation of many organic substances, by the discovery and use of compounds enerically called "oxidation inhibitors or antioxidants. These agents, mostly oxidizable organic compoundsretard the autocatalytic process. Since antioxidants are themselves oxidized in the course of time, as a result of autooxidation, the beneficial effect, obtained by their use, is not permanent and they protect the organic substances only so long as they are not rendered inactive. They are, moreover, very specific in action, each group of auto-oxidizable substances requiring a difierent type of antioxidant for the best results.

Vanadium, chromium, manganese, iron, cobalt, copper and their catalytically active compounds accelerate the rate of oxidation of many organic substances. For example, it is well'known that the advantage gained under this circumstance is seldom worth thecost of the increased quantity of antioxidant required for adequate stabilization, and (3) the suppression of the catalytic activity of the metal compounds by chemical means without physically removing them from the system.

It is an object of the present invention to retard the deterioration of organic substances caused by the action of molecular oxygen and promoted by the presence of certain'metal catalysts and their catalytically active compounds. Another object is to render antioxidants, which are relatively ineffective in the presence of metal catalysts and their catalyticallylactive compounds, efiective to inhibit the oxidation of oxidizable organic substances even in the presence of metal catalysts copper compounds speed the formation of gum in cracked gasoline and the aging of rubber; that cobalt compounds promote the oxidation of drying oils; and that iron compounds catalyze the deterioration of lubricating oils. They also accelerate the oxidation of aromatic hydroxy and amino antioxidants, used to stabilize these oxidizable substances. Hence, these metal catalysts and the antioxldants'are antagonistic in action, and the nor mal inhibiting elfect of the latter is duced in the presence of the former.

Metal compounds occur naturally in many organic products, but often in such slight traces as to cause very little harm. Their concentrations, however, are frequently raised during the course of handling and utilizing the products; vessels and conduits, made of metals containing copper or greatly reiron, are used for storage and transportation, or

ingredients, contaminated with metal compounds,

might be added.

The harm done by these extraneous catalysts may be prevented by at least three methods: (1) their removal by Purification, but often this is practically impossible of accomplishment and usually too costly to be economically feasible, (2), the addition of a sumcient amount of an antioxidant so that its preserving eflect is equal to or greater than the pro-oxidant eflects of the metalcatalysts present, but the effectivenessor the antioxidant is so greatly diminished by the metal catalysts that and their catalytically active compounds. A further object is to provide a new class of metal de activators which are effective to render metal catalysts inactive to catalyze the oxidation of oxidizable organic substances containing or in contact with such metal catalysts. A more particular object is to inhibit the deterioration of petroleum hydrocarbons in the presence of metal catalysts and their catalytically active compounds. Other objects are to provide new compositions of matter and to advance the art. Still other objects will appear hereinafter.

The above and other objects may be accomplished in accordance with my invention which.

comprises adding to organic substances, normally subject to deterioration caused by the action of molecular oxygen, and containing acatalyst 0f the group consisting of vanadium, chromium, manganese, iron, cobalt, copper and their compounds, normally effective to catalyze oxidation of said organic substances, a metal deactivator in a small proportion sufllcient to deactivate such catalyst, such metal deactivator being identical with the compound obtained by condensing one mole of an ortho-hydroxy substituted aldehyde, aromatic in nature, with one mole of a primary monoamino polyhydric alcohol. The organic substance also may, and generally will, contain an antioxidant which is normally efiective to retard oxidation of the organic substance in the absence of the metal catalyst. I have found that such metal deactivators are capable of efiectively suppressing the catalytic activity of vanadium, chromium, manganese, iron, cobalt, copper and their catalytically active compounds and hence will render such catalysts ineffective to catalyze the oxidation of the organic substance. including any antioxidant which may be present.

The organic substances,

' and vegetable fats and oils, edible oils, fruit and vegetable juices, textile fibres, photographic dewhich may be treated in accordance with my invention, include animal the like. My" metal deactivators are particularly desirable in liquid petroleum hydrocarbons and especially in gum-forming hydrocarbon distillates, such. as, for example, cracked gasoline.

Generally, in practice, the organic substance, particularly the petroleum hydrocarbons, will also contain an antioxidant which is normally efiective to materially retard the deterioration or oxidation of the organic substance in the absence of the catalytically active metals, but which is less 7 effective in the presence of such metals.

The metal deactivators of my invention are new chemical compounds, and may be prepared by reacting one mole of an ortho-hydroxy substi-' tuted aldehyde, aromatic in nature, with a primary monoamino polyhydric alcohol in equal molecular proportions and generally in an inert mean one in which the hydroxy group and the aldehyde, or -CIQ, group are directly bonded to adjacent ring caroon atoms. By the term aldehyde, aromatic in nature, I intend to include the unsaturated cyclic aldehydes, such as the pyridine and quinoline aldehydes which have many of the characteristic properties of the aromatic aldehydes, as well as the strictly aromatic aldehydes in which the hydroxy and aldehyde groups are bonded to ring carbon atoms of a benzene ring. I Y

The aldehyde is preferably an. aromatic aldehyde and may contain as substituents hydroxy, alkyl, aryl, alkoxy, aryloxy, halogen, heterocyclic, amino, cyano, carboxyl, sulfonic and like groups. However, I particularly prefer the ortho-hydroxysubstituted aryl aldehydes which are aromatic aldehydes which, except for the hydroxy and aldehyde-groups, consist of carbon and hydrogen.

Also, I particularly prefer the ortho-hydroxy aromatic and ortho-hydroxy aryl aldehydes of the benzene series, by which I mean those which contain one benzene ring and no other cyclic rings. I especially prefer compounds derived from salicylaldehyde.

- By a primary monoamino polyhydric alcohol, I mean an alcohol which contains only one amino group, which amino group must be a primary .amino group, and at least 2 hydroxy groups.

While the amino alcohols, which contain only one hydroxy group, have some eflect, I have round that those, which contain a plurality of hydroxy groups, are much more effective. I' prefer that the amino alcohols be those which, except for the amino and hydroxy groups, consist oi carbon and hydrogen. I particularly prefer that the amino alcohol be a sugar amine which contains a single primary amino group. By sugar amines," I mean-the amines of reducing sugars 015 or more carbon atoms. Such sugar amines may be considered to be amino alcohols of or more carbon atoms with a hydroxy group on each carbon other than that which is-attached to the nitrogen. The

preferred sugar amine is glucamine which is the" primary monoamine derived irom glucose 1.0% will generally be employed.

Definite operative concentrations of the metal deactivator in the organic substance cannot be specified for each case as the quantity required is dependent upon the amount of metal catalyst present in the organic substance. The metal deactivator should be present in the proportion of approximately 5 to 50 times the amount of the metal catalyst present, on the basis of the metallic element, in order to abtain complete deactivation of the metal catalyst. Higher proportions of metal deactivator may be employed, particularly when a reservoir of metal is present in the form of metal in bulk in contact with the organic substance. Generally, from about 0.001% to about 0.1%, based on the weight of the organic substance, will be suiiicient for most purposes,

- particularly when the organic substance is a liquid petroleum hydrocarbon, such as a gum-forming hydrocarbon distillate oi the character of cracked gasoline. In rubber, about 0.1% to about The catalytically active metl and its compounds may be dissolved in the organic substance or suspended therein or may be in the form of metal in bulk in intimate contact with the organic substance. Itwill be understood that, when I refer to an organic substance containing a catalyst, I mean to include those cases wherein the metal in bulk form is in contact with the organic substance, as well as those cases wherein the catalytically active metal is dissolved or suspended in the organic substance.

The deactivators may be added to the oxidizable organic substances to be protected in any form and manner. They may be in solid or liquid form, mixed with other addition agents or dissolved in a solvent. They may be dissolved in the organic substance or dispersed therein in any suitable manner. They may be added to the finished organic substanceor to the organic substance at any stage in its manufacture.

In order to avoid confusion arising from a superabundance'of data, gasoline has been selected' as an example of an auto-oxidizable organic substance for the purposes of illustration. The samples of gasoline used in the following tests were either cracked gasolines or blends of cracked and straight-run gasolines, completely refined, but otherwise untreated with chemical agents, such as dyes, anti-knocks and antioxidants. Since gasoline is a mixture of variable composition, identical results are not obtained with different samples. The magnitude of the effects is great enough, however, to render this difference relatively insignificant. f

p-Benzylaminophenol, abbreviated BAP, has been chosen as a representative gasoline antioxidant. The concentrations of the antioxidants and, the metal deactivators are given in weight percent in gasoline. The concentrations of t e metals are given in parts per million by weight of the metal, abbreviated p. p. m., rather than by weight of the metal compound.

described in J. I. E. C. 25, 397 (1933). It consists in heating cc. 0! gasoline at 100 C. in a 1 liter Pyrex flask containing pure oxygen. The

7 internal pressure is observed every 10 minutes by means of a manometer attached to the sys-- [Induction period of control, 80 minutes. This Table I 0.00l% BAP and having an induction perl oi the absence of copper, was used for these tests.]

300 minutes in Induction iodin minu t s +0.01% salicylalbeta-hydrox eth am 0 Area of metallic copper surface No deactivator 0.5 sq. in '10 160 It will be noted that the above compound counteracts, only partially, the eflect of copper.

Table II gasoline, containing 0.001% BAP and having an induction period 210 minutes in the absence of copper. was used for these tests] Induction period in minutes salicylal glucamine Area of metallic copper surface N 0 deacti 'ator It will be observed that the catalytic eiTect of metallic copper is not only completely suppressed by salicylal gluca'mine, but the induction period is increased beyond 210 minutes to 320 minutes. This is thought to be due to the catalytic metals already present in the gasoline. It is also seen, by comparing the data in Table I and II, that a polyhydroxylated amine forms a more efiective deactivator than'a monohydroxylated amine.

Copper is one of the most potent catalysts for the oxidation of many organic products. It is the most powerful and one of the commonest metal contaminants in gasoline. Other metals, however, possess difierent degrees of catalytic activity.

The action of certain catalysts on stabilized [Induction period or control, 100 minutes. Thi gescline, containing gasoline and the efiect of salicylal glucamine on their activity are shown in Table III.

Table III [Induction period of control, 130 minutes. This gasoline, contalnin 0.002592, p-(n-butylamino) phenol and having an induction rl of 390 m nntes in the absence of metal catalysts, was used or the tests the results of which are presented below.]

Induction period in minutes Conc. N Metal catalyst Presence of Absence of 0.006 ssideactivator icy 8 camine [The metal catlystl were added as the 010ml.

It will be noted that chromium, manganese, iron and cobalt shorten the induction period of gasoline stabilized with p-(n-butylamino) phenol, and that salicylal glucamine counteracts the action of all these metals.

The deactivators are also enective in decreasing the copper dish gum in gasoline, whether used alone or in combination with an antioxidant.- This is shown by thedata in Table IV.

It has long been recognized that small traces of copper have a very pronounced catalytic effecton the oxidation of rubber. In order to overcome this difilculty, it has been necessar to establish rigorous specifications for the copper content of compounding agents used in rubber. In many cases, particularly with dyes, the removal of traces of copper is both troublesome and expensive.

In general, the common antioxidants, used in rubber, are unable to suppress the catalytic action of copper. The metal deactivators, however, have been found to be effective for this purpose.

Since salicylal glucamine is not an antioxidant it was tested in stock containing 1% of phenylbeta-naphthylamine as an added antioxidant; The bomb physical test was used as a method of evaluation. The following stock was used in the tests, wherein the parts are by Weight.

The stock was cured for 45 minutes at 40 pounds steam pressure. The results of the tests are given in Table V.

Table V Da sat No deacti- 0.67 salicyl- Glucamine No. 23 ig vator tensile, g? al tensile, elongation,

oxygen lbs/sq. in. lbsJsq. in. percent 1 0 0 650 3,350 050 2 2 1,525 000 3,000 630 3 5 Melted oil. 2, 400 610 4 7 1,976 655 5 9 1, 625 480 6 l2 l, 275 455 7 14 1,025 420 8 10 975 410 9 19 800 370 10. 21 750 300 The deactivators, belonging to the class of'compounds of my invention, are readily prepared by I reacting equimolarproportions of ortho-hydroxy aromatic aldehydes and hydroxyamines. in a suitable solvent if necessary.

One method of preparing salicylal glucamine is I as follows: An aqueous solution was mixed with 24 parts of salicylaldehyde and evaporated on a steam bath until the reaction mixture had become a paste. Bright yellow crystals were obtained by adding methanol to the reaction mixture. The crystals were filtered and dried. They melted at.181-2 C. and contained 4.9% nitrogen by weight.

It is thought that the following reaction occurred.

Q0130 Nnr-on'rcnomi-cmon Sallcylaldehyde Glucamlne CH=N-CH:(CHOH)4CH:OH HgO H Salicylal glucamine Water Most of these deactivators are yellow compounds which are hydrolyzed by mineral acids.

In order to obtain the best results, the deactivators must be soluble in the products to be protected.

Since many of these deactivators, particularly the condensation products of the polyhydroxyamines, are water soluble, they are especially useful in stabilizing systems containing considerable proportions of water, such as aqueous solutions, 4 suspensions and emulsions.

It will be understood that the experiments and tests, hereinbefore given. have been given for illustrative purposes only. Many variations and modifications can be made in my invention without departing from the spirit or scope thereof.

Aldehydes 2-hydroxy-benzaldehyde 2-hydroxy-5-chlorobenzaldehyde Z-hydroxy-3,5-dibromobenzaldehyde 2-hydroxy-3-nitrobenzaldehyde Z-hydroxy-B-methylbenzaldehyde 2-hydroxy-5-ter-butylbenzaldehyde 2-hydroxy-3-methoxybenzaldehyde 2,4-dihydroxybenzaldehyde 2-hydroxynaphthaldehyde-I 1-hydroxynaphthaldehyde-2 Anthrol-2-aldehyde-1 Z-hydroxyfiuorene-aldehyde-1 4-hydroxydiphenylaldehyde-3 3-hydroxyphenanthrene-aldehyde-4 H ydrozyamines 3-aminopropanediol-1,2 2-amino-2-methylpropanediol-1,3 2-amino-2 methylolpropanediol-1,3 5-amino-1,2,3,4-tetrahydroxypentane 2-aminol,1,1-trimethylolethane Ara'binamine Xylamine Mannamine Galactamine Glucamine Fructamine Ribamine Lyxamine Lactamine Rhamnamine Sorbinamine Sorbamine Gulamine Talamine It will be apparent that, by my invention, 1 am able to effect the stabilization of organic substances susceptible to the harmful action of molecular oxygen catalyzed by vanadium. chromium, manganese, iron, cobalt, copper and their catalytically active compounds. This stabilization may be accomplished, in accordance with my in-' vention, by the addition of metal deactivators. either alone or in combination with an amount of an antioxidant suflicient to stabilize the substance in'the absence of metal catalysts. It is often technically and economically unfeasible to counteract the catalytic effects of such metals by means of an antioxidant alone. I believe that the metal deactivators of my invention function by forming very stable complexes with the metals, which complexes are catalytically inactive. It appears that the metal deactivators of my invention, in general, are not antioxidants. How- I ever, my invention is not to limited by any theory as, to the manner in which the metal deactivators function to produce the results.

This is adivision of my co-pending application Serial No. 472,159, filed January 12, 1943, for Stabilization of organic substances."

I claim:

1. Salicylal glucamine.

2. A compound of the formula wherein R represents an ortho-divalent aromatic radical and R represents a polyhydroxy aliphatic radicalcontaining at least 5 carbon atoms with a hydroxyl group .on each carbon other than the carbon attached to N.

3. A compound of the formula wherein R represents an ortho-divalent aromatic wherein R represents an ortho-divalent aromatic radical and R represents a polyhydroxy aliphatic radical containing at least 5 carbon atoms with a hydroxyl group on each carbon other than the carbon attached to N and consisting of the elements carbon, hydrogen and oxygen. 5. A compound of the formula wherein R represents an ortho-divale'nt arylene radical of the benzene series consisting of the elements carbon and hydrogen and R represents a polyhydroxy aliphatic radical containing at least 5 carbon atoms with a hydroxyl group on each carbon other than the carbon attachedto Rand consisting of the elements carbon, hydrogen and oxygen.

6. A compound of the formula anew A "15 wherein R'repreaentn a polyhydroxy' aliphatic whereinR represents an ortho-divalent aromatic radical containing at least 5 carbon atoms with A radical.

a zgouptgn each carbon other than the v 9. A compound of the formula car na ed N. '1. A compound of the formula v e HO R' CH"N CH' (CHOH) wherein R repreents an ortho-divalent aromatic radical of the benzene series. H 10. A compound of the formula wherein R represents apolyhydtoxy aliphatic lie-R (CHOHH CHQOH radical containing at least 5 carbon atoms with wherein R represente an ortho-divalent' aromatic a hydroxyl group on each carbon other than the radical of the benzene series conslsting'o! the ele- 'carbon attached to N and consisting of theelev ments carbon and hydrogen.

mentc carbon, hydrogen and oxyzen.

a. Acompound oi thei'ormula u I IVAN'GUBELMANN. no-R-cH=N-cm-(cHonn-cm0r1 

